Part of printing machine



FIG. 1 is a perspective view of a part of a printing machine showing our new design;

FIG. 2 is a front view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a right view thereof;

FIG. 5 is a left view thereof;

FIG. 6 is a rear view thereof; and,

FIG. 7 is a bottom view thereof.

The portions of the part of the printing machine shown in broken lines form no part of the claimed design. 

CLAIM The ornamental design for a part of a printing machine, as shown and described. 